Competitive Exploitation of Soil Water by Five Eastern North American Tree Species

Abstract

We have examined water status and rates of water loss from the soil and plants for a growing season in a dry ridge-top community near Ithaca, New York. Species differences in stomatal response to LWP and in the dependence of LWP on SWP and VPD caused various transpiration patterns with time in the species studied As the soil dried, the more drought-adapted species on the site reduced transpiration less than did the less drought-adapted species This maintenance of high transpiration by the more drought-adapted species promoted soil water loss to the detriment of the net carbon uptake and survival of other species. The least drought-adapted species were most susceptible to this competitive exploitation of soil water.